2. SELECTING SUITABLE SITES FOR A HATCHERY

2. SELECTING SUITABLE SITES FOR A HATCHERY
Prior to the establishment of any shrimp hatchery, it is of primary importance to carry out a thorough feasibility study to determine the suitability of the proposed site. The main criteria followed are water quality, availability of spawners and site accessibility.
For establishing large-scale modern hatcheries, the criteria for hatchery site selection must be rigidly followed because it is costly to change site when high financial inputs have already been committed. However, site selection for smaller hatcheries are less rigid than the bigger ones.
2.1 Criteria in the selection of a suitable site for a hatchery
2.1.1 Sea water supply
The sea water used in a hatchery should be clean, clear and relatively free from silt. The water quality should be stable with minimal fluctuation in salinity. Suitable sites are usually found in sandy and rocky shore ecosystem where there is clean, clear and good quality sea water all year round. Sites not suitable for hatchery are swamps and muddy shores where the water becomes turbid during heavy rains or due to turbulence. Avoid river mouths where abrupt lowering of salinity often occurs during heavy rainfall. An added advantage of rocky and sandy shores is that good quality sea water is relatively near the shoreline thus reducing the cost of piping installation and pumping cost. The hatchery site should also be free from possible impact from any inland water discharges containing agricultural or industrial waste.
2.1.2 Availability of spawners
Presence of spawners at the vicinity of the proposed site is of considerable advantage in ensuring consistent supply of spawners, reducing the cost of transportation which could affect the rate of spawning.
2.1.3 Availability of power source
Electricity is essential to provide the necessary power to run equipment and other life support systems in the hatchery. Although some marine pumps and aerators can be driven directly by handy generators, the shrimp hatchery can therefore be operated in areas without electricity supply. However, it is more economical to operate it in areas where there is a reliable source of electricity. Installation of an on-site standby generator is absolutely necessary especially in areas where there are frequent lengthy power failures and fluctuations.
2.1.4 Freshwater supply
Freshwater is essential for daily hatchery operation such as salinity adjustment, equipment maintenance and for domestic use.
2.1.5 Accessibility
Ideally, a hatchery should be sited in areas where there are active shrimp farming operations so that the shrimp larvae produced can be easily transported and distributed to the grow-out ponds. Hence, the site chosen for hatchery establishment must be easily accessible to facilitate communication and transportation.
2.1.6 Climatic conditions
A hatchery can be established in any climatical condition as long as the required rearing conditions can be adequately provided. However, all the commercial hatcheries take full advantage of nature in terms of energy source and supply of good quality water. Sunlight is the basic requirement for hatchery operations especially in the mass production of natural food used as feeds for the growing shrimp larvae. In the temperate region where adequate sunlight is only available in certain periods of the year, hatchery operations are usually confined to a certain suitable season. This is especially so in the case of some marine shrimps such as Penaeus japonicus and P. orientalis which have a single pronounced spawning season. In such situations, hatchery production is relatively limited to a short period of time. On the other hand, the tropics are endowed with warmer climate with adequate sunlight all year round and has ideal climatic conditions for hatchery operation especially for many warm water species such as the tiger shrimp, Penaeus monodon, the white shrimp, P.indicus which spawn all year round. The optimal temperature for hatchery design may be necessary in areas where there are pronounced long period of rainfalls which often reduces the intensity of light, cause turbidity in water supply and lowering of water temperature.

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